[unreadable] Ultrasound (US) is the imaging modality of choice for fetal evaluation. However, there are many cases in which US is nonspecific. With an R29 awarded to investigate the potential of ultrafast magnetic resonance imaging (MRI) in fetuses with central nervous system (CNS) abnormalities, we developed a protocol that reliably images the fetus without fetal or maternal sedation and found that MRI commonly changed diagnoses, counseling, and management. However, further development is needed, especially in fetuses with ventriculomegaly (VM). Fetuses with VM are a heterogeneous population, and it is likely that using additional MR data regarding overall ventricular appearance, cortical appearance, and cortical and ventricular volumes; and comparing these data to outcomes, that we can improve counseling and management of patients. The overall hypothesis to be addressed in the proposed grant is: The use of MRI and additional MRI indices will improve the diagnostic utility of MR and the ability to predict outcomes compared to a reliance on US data alone. [unreadable] Specific Aim #1: To determine whether, in comparison to US alone, additional qualitative MRI information adds clinically useful information with respect to immediatepostnatal outcome in fetuses with VM. [unreadable] Specific Aim #2: To determine whether or not additional qualitative and quantitative indices available with MR correlate with cognitive and motor development of the infant as assessed by standardized developmental assessment tools for cognitive, motor, and psychosocial development, more closely than routine prenatal US alone. Patients referred for MR with US diagnosis of VM will be recruited. In addition to morphologic analyses by US and MR, the ventricular appearance, cortical development, cortical volume, ventricular volume, and cortical thickness will be assessed. Postnatal cognitive and motor testing will be performed for 3 years. The US data, standard MR data, and expanded MR data set will be analyzed for correlation with outcomes. We hypothesize that use of the increased data from fetal MR will allow for identification of a group of fetuses with mild VM that have normal outcomes. The results of this project have the potential to benefit the practice of radiologists, obstetricians, pediatricians, neonatologists, and pediatric neurologists involved in the care of pregnant women with fetuses with VM. [unreadable] [unreadable]